Leaf decomposing fungi influence growth across carbon environments.

is a model organism in ecology and evolution. However, its metabolism in its native habitat remains mysterious: it is frequently found growing on leaf litter, a habitat with few carbon sources that can metabolize. We hypothesized that leaf-decomposing fungi from the same habitat break down the cellulose in leaf litter extracellularly and release glucose, supporting growth.

Yeasts from temperate forests.

Yeasts are ubiquitous in temperate forests. While this broad habitat is well-defined, the yeasts inhabiting it and their life cycles, niches, and contributions to ecosystem functioning are less understood. Yeasts are present on nearly all sampled substrates in temperate forests worldwide.

Forest are robust to seasonal biotic and abiotic changes.

Microorganisms are famous for adapting quickly to new environments. However, most evidence for rapid microbial adaptation comes from laboratory experiments or domesticated environments, and it is unclear how rates of adaptation scale from human-influenced environments to the great diversity of wild microorganisms. We examined potential monthly-scale selective pressures in the model forest yeast .

Defining and Disrupting Species Boundaries in .

The genus is an evolutionary paradox. On the one hand, it is composed of at least eight clearly phylogenetically delineated species; these species are reproductively isolated from each other, and hybrids usually cannot complete their sexual life cycles. On the other hand, species have a long evolutionary history of hybridization, which has phenotypic consequences for adaptation and domestication.

Quantifying the efficiency and biases of forest Saccharomyces sampling strategies.

Saccharomyces yeasts are emerging as model organisms for ecology and evolution, and researchers need environmental Saccharomyces isolates to test ecological and evolutionary hypotheses. However, methods for isolating Saccharomyces from nature have not been standardized, and isolation methods may influence the genotypes and phenotypes of studied strains. We compared the effectiveness and potential biases of an established enrichment culturing method against a newly developed direct plating method for isolating forest floor Saccharomyces spp.

The ecology of killer yeasts: Interference competition in natural habitats.

Killer yeasts are ubiquitous in the environment: They have been found in diverse habitats ranging from ocean sediment to decaying cacti to insect bodies and on all continents including Antarctica. However, environmental killer yeasts are poorly studied compared with laboratory and domesticated killer yeasts. Killer yeasts secrete so-called killer toxins that inhibit nearby sensitive yeasts, and the toxins are frequently assumed to be tools for interference competition in diverse yeast communities.

Superior Dispersal Ability Can Lead to Persistent Ecological Dominance throughout Succession.

A large number of descriptive surveys have shown that microbial communities experience successional changes over time and that ecological dominance is common in the microbial world. However, direct evidence for the ecological processes mediating succession or causing ecological dominance remains rare. Different dispersal abilities among species may be a key mechanism.

Modeling the contributions of chromosome segregation errors and aneuploidy to Saccharomyces hybrid sterility.

Errors in meiosis can be important postzygotic barriers between different species. In Saccharomyces hybrids, chromosomal missegregation during meiosis I produces gametes with missing or extra chromosomes. Gametes with missing chromosomes are inviable, but we do not understand how extra chromosomes (disomies) influence hybrid gamete inviability.

Evidence for microbial local adaptation in nature.

Local adaptation is an outcome of divergent selection on microbial populations and has been linked to the immense genetic diversity of microbes observed in nature. Because it is difficult to study microbes in their natural habitats, most tests of microbial local adaptation have been performed in model laboratory systems; as a result, microbiologists have limited understanding of local adaptation among natural microbial populations. In this review, we summarize the evidence for microbial local adaptation in nature.

Measuring microbial fitness in a field reciprocal transplant experiment.

Microbial fitness is easy to measure in the laboratory, but difficult to measure in the field. Laboratory fitness assays make use of controlled conditions and genetically modified organisms, neither of which are available in the field. Among other applications, fitness assays can help researchers detect adaptation to different habitats or locations.

Fungal diversity and ecosystem function data from wine fermentation vats and microcosms.

Grape must is the precursor to wine, and consists of grape juice and its resident microbial community. We used Illumina MiSeq® to track changes in must fungal community composition over time in winery vats and laboratory microcosms. We also measured glucose consumption and biomass in microcosms derived directly from must, and glucose consumption in artificially assembled microcosms.

Age-related cellular changes in the long-lived bivalve A. islandica.

One of the biggest challenges to studying causes and effects of aging is identifying changes in cells that are related to senescence instead of simply the passing of chronological time. We investigated two populations of the longest living non-colonial metazoan, Arctica islandica, with lifespans that differed sixfolds. Of four investigated parameters (nucleic acid oxidation, protein oxidation, lipid oxidation, and protein instability), only nucleic acid oxidation increased with age and correlated with relative lifespan.

The ecology and evolution of non-domesticated Saccharomyces species.

Yeast researchers need model systems for ecology and evolution, but the model yeast Saccharomyces cerevisiae is not ideal because its evolution has been affected by domestication. Instead, ecologists and evolutionary biologists are focusing on close relatives of S. cerevisiae, the seven species in the genus Saccharomyces.

Inoculum potential of Rhizopogon spores increases with time over the first 4 yr of a 99-yr spore burial experiment.

In disturbed or pioneer settings, spores and sclerotia of ectomycorrhizal fungi serve as the necessary inoculum for establishment of ectomycorrhizal-dependent trees. Yet, little is known about the persistence of these propagules through time. Here, live field soil was inoculated with known quantities of basidiospores from four pine-associated species of Rhizopogon; these samples were then buried in retrievable containers, and pine seedling bioassays of serially diluted spore samples were used to measure spore viability.